Actually, there is something at the core of most of the major religions that seems to be relatively consistent: 'Be good to each other, live a good life, and something good will be waiting for you in the afterlife.' This core doesn't require that one believe in any specific deity (although belief in an afterlife or reincarnation helps with the last part - I suppose that could be generalized to 'the future'.)

Just becaue the sucessful religions had this philosophy it does not mean all of them did, but its not a stretch of the imagination that the religions that promote coperation would be the ones to survive the long haul rather than the ones internally destructive.

Buddhism is less about "being good to each other" and more recognizing the inherent problems with attributing "good" and "evil" to actions taking place in the illusory world in which we currently exist prior to transcending, and that one's dharma en route to that final destination - which takes much longer for some to reach than others - may involve doing things less than sugar, spice and everything nice in this world in order to move on to the next and, indeed, to enable others to progress also.

Granted it's a very rough and messy paraphrasing, but the point is that no, living a good life as we would recognize it is no assurance of spiritual reward in that system. There's an altogether different pattern of balances at work there.